This invention relates to a cathodic protection system to maintain a submersible metal unit of a marine transportation system at a selected potential to reduce or eliminate corrosion thereto.
Marine drive units are commonly formed of metal such as aluminum for example which may become corroded when subjected to various operating environments, such as within salt water. Known systems have supplied controlled amounts of energy to an anode positioned in close proximity to the drive unit in response to the sensed potential monitored by a reference electrode also positioned in close proximity to the drive unit. In such manner, controlled amounts of energy are supplied to maintain the drive unit at a prescribed protective polarization to retard or prevent corrosive action. One desirable cathodic protection system is disclosed in U.S. Pat. No. 3,953,742 to Edward P. Anderson and Mark Harris, and is assigned to a common assignee herewith.